Replace `println!` calls on the results paths with `writeln!` on
`io::stdout()` and propagate the `io::Error` to `main`, where
`ErrorKind::BrokenPipe` is turned into a quiet `exit(0)`. This matches
the conventional behavior of command-line tools when their output pipe
is closed early (e.g. `hyperfine ... | head -n 0`), and fixes panics in
all run-output paths: the per-benchmark header and results, the speed
comparison summary, and `-`-style exports to stdout. The warnings and
"Note" outputs to stderr are converted the same way.
---------
Co-authored-by: Mathjk <Mathjk@users.noreply.github.com>
Co-authored-by: David Peter <mail@david-peter.de>
Extend the --runs=N option added in d78c33b (Added options to specify
the max/exact numbers of runs., 2018-09-09) to support --runs=1
instead of dying with a usage error.
This is useful to do ad-hoc testing of your commands while they might
still have syntax errors, or just for doing one run where you don't
care about the stddev.
Before:
$ /usr/bin/hyperfine -s basic -r 1 -L n 5,10 'sleep 0.{n}'
Error: Number of runs below two
After (-s basic) also works:
$ hyperfine -r 1 -L n 5,10 'sleep 0.{n}'
Benchmark 1: sleep 0.5
Time (abs ≡): 500.6 ms [User: 0.6 ms, System: 0.0 ms]
Benchmark 2: sleep 0.10
Time (abs ≡): 100.8 ms [User: 0.7 ms, System: 0.0 ms]
Summary
'sleep 0.10' ran
4.97 ± 0.00 times faster than 'sleep 0.5'
This likewise combines correctly with -m and -M, probably not very
useful, but if you're tweaking an existing command-line:
$ hyperfine -m 1 -M 1 -L n 5,10 'sleep 0.{n}'
Benchmark 1: sleep 0.5
Time (abs ≡): 500.6 ms [User: 0.5 ms, System: 0.0 ms]
Benchmark 2: sleep 0.10
Time (abs ≡): 100.6 ms [User: 0.6 ms, System: 0.0 ms]
Summary
'sleep 0.10' ran
4.98 ± 0.00 times faster than 'sleep 0.5'
The "± 0.00" output in "faster than" should probably be adjusted too,
or we could keep it for consistency. I didn't implement that because
this is the first time I do anything in Rust, and I ran out of
template to copy when wanting to quickly implement this in
write_benchmark_comparison() in main.rs.